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Crystal Opal

A variety of 'Precious Opal' [Opal]
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03102650017743898137082.jpg
Crystal Opal

Coober Pedy, Pastoral Unincorporated Area, South Australia, Australia
02718510017271929142060.jpg
Crystal Opal

Coober Pedy, Pastoral Unincorporated Area, South Australia, Australia
03102650017743898137082.jpg
Crystal Opal

Coober Pedy, Pastoral Unincorporated Area, South Australia, Australia
02718510017271929142060.jpg
Crystal Opal

Coober Pedy, Pastoral Unincorporated Area, South Australia, Australia
03102650017743898137082.jpg
Crystal Opal

Coober Pedy, Pastoral Unincorporated Area, South Australia, Australia
04073990017271929168051.jpg
Crystal Opal

Coober Pedy, Pastoral Unincorporated Area, South Australia, Australia
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About Crystal OpalHide

Formula:
SiO2 · nH2O
Name:
The origin of the word "opal" is uncertain. It may be from the Sanskrit "upala", meaning "stone" or "precious stone" or from opalus, the ancient Latin name for the gem (Pliny the Elder, 75-79). Pliny may have also referred to the gem as paederos, but a modern commentary by Kostov (2008) questions if that name was actually applied to the opal in the modern sense.
A transparent to translucent variety of Precious Opal where the colour play is visible both on the surface and in the interior.

Visit gemdat.org for gemological information about Crystal Opal.



Unique IdentifiersHide

Mindat ID:
8003 (as Crystal Opal)
3004 (as Opal)
Long-form identifier:
mindat:1:1:8003:9 (as Crystal Opal)
mindat:1:1:3004:1 (as Opal)

Chemistry of Crystal OpalHide

Mindat Formula:
SiO2 · nH2O
Element Weights:
Element% weight
O61.458 %
Si35.961 %
H2.581 %

Calculated from ideal end-member formula.
O
Si
H
Elements listed:
H, O, Si - search for minerals with similar chemistry

Other InformationHide

Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

Internet Links for Crystal OpalHide

References for Crystal OpalHide

Localities for Crystal OpalHide

Showing 6 localities.

This map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the symbol to view information about a locality. The symbol next to localities in the list can be used to jump to that position on the map.
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Locality ListHide

- This locality has map coordinates listed. - This locality has estimated coordinates. ⓘ - Click for references and further information on this occurrence. ? - Indicates mineral may be doubtful at this locality. - Good crystals or important locality for species. - World class for species or very significant. (TL) - Type Locality for a valid mineral species. (FRL) - First Recorded Locality for everything else (eg varieties). Struck out - Mineral was erroneously reported from this locality. Faded * - Never found at this locality but inferred to have existed at some point in the past (e.g. from pseudomorphs).

All localities listed without proper references should be considered as questionable.
Australia
 
  • New South Wales
    • Finch Co.
www.mindat.org (n.d.)
  • Queensland
    • Paroo Shire
  • South Australia
    • Aṉangu Pitjantjatjara Yankunytjatjara (APY; APY Lands)
      • Mintabie
    • Pastoral Unincorporated Area
USA
 
  • Nevada
    • Humboldt County
  • Oregon
    • Morrow County
USGS
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